1 files changed, 123 insertions, 0 deletions

diff --git a/server/helpers/activitypub.ts b/server/helpers/activitypub.ts
new file mode 100644
index 000000000..ecb509b66
--- /dev/null
+++ b/server/helpers/activitypub.ts
@@ -0,0 +1,123 @@
+import * as url from 'url'
+
+import { database as db } from '../initializers'
+import { logger } from './logger'
+import { doRequest } from './requests'
+import { isRemoteAccountValid } from './custom-validators'
+import { ActivityPubActor } from '../../shared/models/activitypub/activitypub-actor'
+import { ResultList } from '../../shared/models/result-list.model'
+
+async function fetchRemoteAccountAndCreatePod (accountUrl: string) {
+  const options = {
+    uri: accountUrl,
+    method: 'GET'
+  }
+
+  let requestResult
+  try {
+    requestResult = await doRequest(options)
+  } catch (err) {
+    logger.warning('Cannot fetch remote account %s.', accountUrl, err)
+    return undefined
+  }
+
+  const accountJSON: ActivityPubActor = requestResult.body
+  if (isRemoteAccountValid(accountJSON) === false) return undefined
+
+  const followersCount = await fetchAccountCount(accountJSON.followers)
+  const followingCount = await fetchAccountCount(accountJSON.following)
+
+  const account = db.Account.build({
+    uuid: accountJSON.uuid,
+    name: accountJSON.preferredUsername,
+    url: accountJSON.url,
+    publicKey: accountJSON.publicKey.publicKeyPem,
+    privateKey: null,
+    followersCount: followersCount,
+    followingCount: followingCount,
+    inboxUrl: accountJSON.inbox,
+    outboxUrl: accountJSON.outbox,
+    sharedInboxUrl: accountJSON.endpoints.sharedInbox,
+    followersUrl: accountJSON.followers,
+    followingUrl: accountJSON.following
+  })
+
+  const accountHost = url.parse(account.url).host
+  const podOptions = {
+    where: {
+      host: accountHost
+    },
+    defaults: {
+      host: accountHost
+    }
+  }
+  const pod = await db.Pod.findOrCreate(podOptions)
+
+  return { account, pod }
+}
+
+function activityPubContextify (data: object) {
+  return Object.assign(data,{
+    '@context': [
+      'https://www.w3.org/ns/activitystreams',
+      'https://w3id.org/security/v1',
+      {
+        'Hashtag': 'as:Hashtag',
+        'uuid': 'http://schema.org/identifier',
+        'category': 'http://schema.org/category',
+        'licence': 'http://schema.org/license',
+        'nsfw': 'as:sensitive',
+        'language': 'http://schema.org/inLanguage',
+        'views': 'http://schema.org/Number',
+        'size': 'http://schema.org/Number'
+      }
+    ]
+  })
+}
+
+function activityPubCollectionPagination (url: string, page: number, result: ResultList<any>) {
+  const baseUrl = url.split('?').shift
+
+  const obj = {
+    id: baseUrl,
+    type: 'Collection',
+    totalItems: result.total,
+    first: {
+      id: baseUrl + '?page=' + page,
+      type: 'CollectionPage',
+      totalItems: result.total,
+      next: baseUrl + '?page=' + (page + 1),
+      partOf: baseUrl,
+      items: result.data
+    }
+  }
+
+  return activityPubContextify(obj)
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  fetchRemoteAccountAndCreatePod,
+  activityPubContextify,
+  activityPubCollectionPagination
+}
+
+// ---------------------------------------------------------------------------
+
+async function fetchAccountCount (url: string) {
+  const options = {
+    uri: url,
+    method: 'GET'
+  }
+
+  let requestResult
+  try {
+    requestResult = await doRequest(options)
+  } catch (err) {
+    logger.warning('Cannot fetch remote account count %s.', url, err)
+    return undefined
+  }
+
+  return requestResult.totalItems ? requestResult.totalItems : 0
+}